Fluid-pressure automatic-brake mechanism



Unire STATES ATnNT Finca,

FLUID-PRESSURE AUTOMATIC-BRAKE MECHANISIVI.

SPECIFICATION forming part of Letters Patent No. 386,514, dated July 24,1888.

Application filed December 5, 1987. Serial No. 257,019. (No model.)

T 0 all whom 25 may concern:

Be it known that I, GEORGE BAYLEY VIL- LIAMs, a citizen of the UnitedStates, residing at La Crosse, in the county of La Crosse and State ofVisconsin, have invented or discovered certain new-and usefulImprovements in Fluid-Pressure Automatic-Brake Mechanism, of whichimprovements the following is a specification.

The object of my invention is to provide for the recharging of theauxiliary reservoirs of the automatic air-brake while the brakes areapplied, without releasing the brakes. or with the release of thebrakes, as may be desired, in order that trains may be enabled todescend dangerous grades with far greater safety and with greater ceonomy in the use of compressed air than with the brakes at present in use,the necessity for delays to adjust the brake mechanism under every carbefore descending dangerous grades, and again after descending suchgrades before the brakes can be entirely released, being also obviatcdby my improvements.

To this cud my invention, generally stated, consists in a novelcombination of a brakepipe, an auxiliary reservoir, a brake-cylinder,and a triple-valve77 device, governing, primarily, communication betweenthe auxiliary reservoir and the brake-cylinder; secondaril y,communication directly from the brake-pipe to the brake-cylinder underthe control of a stop-cock, and, thirdly, communication directl y fromthe brake-pi pc or main air-pipe to the auxiliary reservoir through anauxiliary channel or pipe provided for this purpose.

It will be readily seen that my invention is an improvement upon theVestinghouse system of automatic ai r-brakes.

The improvements claimed are hereinafter fully set forth.

The objections to the present Vestinghouse automatic air-brake are thataf ter the brakes have been applied the auxiliary reservoirs cannot berecharged without a waste of air in partially releasing the brakesi thatin such case the brakes would be entirely released but for the use of apressure-retaining valve governing the exhaust-outlet of the triplevalve on every ear; that the use of such pressureretaining valverequires that the train be stopped and the valve adjusted on every carbefore descending a dangerous grade, which operation has to be repeatedafter the descent of such grade before the brakes can be fully released;that theaecidental moving of plug of pressure-retaining valve tocut-off, or the loss of such plug, followed by a wooden plug beingtightly driven in by a well-meaning brakeman, would prevent any releaseof the brakes and cause all the wheels to slide and be ruined, and thatan auxiliary engincers valve has to be used in order to keep the brakesapplied on the locomotive driving-wheels, while the auX- iliaryreservoirs are being recharged and the brakes partially released on thecars. These various defects, and the danger resulting from allowing theauxiliary reservoirs to become gradually exhausted while descendingdangerons grades, are entirely eliminated by myimprovement.

I am aware that Charles I-I. Perkins, in Patent No. 163,242, described amethod of recharging the auxiliary reservoirs without releasing thebrakes by means of his improvement, and I am equally well aware that hisimprovement is not constructed on corrcctmechanical principles to enableit to satisfactorily perform this operation. My improvelnent is,however, entirely different from his, and is properly adapted tosatisfactorily perform what is claimed for it.

Reference is to be had to the accompanying drawing, which is a verticalcentral sectional view of a triple valve embodying my improvements, andwhich forms a part of this specification.

A represents the upper cap, and B thc lower cap, of the triple Valve,which together form the triple-valve case, having a channel, l, leadingfrom main air-pipe through nipple 2 and channel 3 into air-chamber 4.From chamber 4 communication is established, through channel or channels5, with valve-chamber 6, which has direct communication at all timeswith piston-chamber 7, in which piston 110perates. From piston-chamber 7communication is established, through a groove,8, in the side ofpiston-chamber, when pistou 11 is at the upper limit of its traverse,with valvechamber 9, which is in direct communication at all times withauxiliary reservoir through channel l0.

In chamber 9 is a slide-valve, 1.2, having a IOO ,3 sessie limited freemotion on stem of piston 11in order to provide for its perfectgraduation, and to neutralize the effects of reaction caused by theengineer allowing a considerable quantity of air to escape from mainair-pipe, and then suddenly closing his brakevalve. Slide-valve 12 has agraduating-valve, 13, and discharge.- ports 14 and 15, adapted forcommunicating with channel 16 during the descent of piston 11, therebyallowing air to pass from auxiliary reservoir to brake-cylinder for thepurpose of applying the brakes. `Slide-valve 12 has also a groove, 17,in its face, adapted for connecting channel 16 with port 18, leading toexhaustsoutlet 19, when piston 11 is at the upper limit of its"traverse, thereby allowing compressed air in the brake-cylinder toescape into the open air to facilitate the release of the brakes.Auxiliary slide-valve 20 similarly controls the admission of compressedair from main air-pipe into brake-cylinder during the descent of pistonl1. It has a graduatingvalve, 21, and a port, 22, adapted forcommunicating with channel 23 during the descent of piston 11, therebyallowing air to pass from main air-pipe or brake-pipe through channel23, three-way cock or other stop-cock 49, chamber 26, check-valve 27,channel 28, and channel 16 into brake-cylinder. When slide-valve 20 isat its extreme lower limit,air will pass over its top into channel 24,leading to brake-cylinder, through groove 25 in cock 49, chamber 26,check-valve 27, and channels 28 and 16. Three-way cock 49 is soconstructed that channels 23 and 24 may both be closed, both left open,or channel 24 only left open, as may be desired for use in eliminatingshock. Slide-valve 23, in combination with 'three-way cock 49,check-valve 27, and the connections through these to brakecylinders,form the subject-matter of applications, Serial Nos. 249,169 and249,170, for Letters Patent of theUnited States filed by me and nowpending, and need not, therefore, be more particularly described herein.The construction herein is somewhat modified and a more sensitive andefficient check-valve, 27, substituted for the spring-actuatedcheck-valve previously used. A case, 29, is provided for doublewingfluidpressure-aetuated check-valve 27. An inner jam-nut, 30, compressesrubber or other suitable packing, 31, closing up holes made in boringchannels 23 and 24. The end of channel 24, communicating directly withchamber 26 when drilled, can be suitably closed by a screw or otherwise,or, if desired, may be left open, leaving channel 23 only to becontrolled by a stopcock.

Auxiliary slide-valve 32, like slide-valves 12 and 20, has a limitedfree motion on stem of piston 11, for the same purpose of providing forits perfect graduation. While, however, this free .motion in valves 12and 20 neutralizes reaction, as they operate only during the downwardtraverse of piston 11, the case is the reverse with slide-valve 32,which operates only during the upward traverse of piston l1; hence itsport 34 must pass so far below discharge-port 35 during the downwardtraverse of piston 11 that reaction may not open communicationV betweenauxiliary reservoir and main air-pipe through channels 10, 38, and 37,while the pressure is greater in auxiliary reservoir than in mainair-pipe, thus causing the air-pressure to become equal in both andchecking the desired application of the brakes. Slidevalve 32 has agraduatingvalve, 33, and a port, 34, adapted for communicating withdischarge-port 35 and allowing compressed air to pass from main airpipethrough chamber 36, channels 37, 38, and 10 to auxiliary reservoir, forthe purpose of recharging the latter without releasing the brakes,during the upward traverse of piston 11, by means of a gradual increaseofpressure, which will equalize on both sides of piston 11, instead oflifting it to the upper limit of its traverse and releasing thebrakes,which would result from admitting air from main reservoir intomain air pipe faster than could pass readily through thespecially-limited size of port 34.

In lower cap, B, is a graduating-piston, 39, actuated by air-pressurepassing from chamber4 through channel 41 into chamber 40, which is animprovement upon the VVestinghouse spring-actuated grad uating-stem. Thepiston-case 43 screws into capnut 42, thus forming graduatingpiston-chamber 40. To prevent compressed air passing from chamber 4 toact on upper side of graduatingpiston 39, rubber or other suitablepacking is held in place against stem of piston 39 by means ofpacking-nut 44. In order to prevent compressed air from acting on upperside ofgraduating-piston 39, in case of leakage around the edge of saidpiston or otherwise, I provide annular groove 47 in capnut 42 andannular groove 48 in piston-case 43, and then drill a channel throughlower cap, B, to groove 47, throughthe sleeve portion of cap-nut 42,thence to groove 48, and thence through the sleeve portion of pistoncase43 to the upper part of pistou chamber 40. The differentialfluidpressure-actuated graduating-piston 39, with case, chamber, andconnections provided for same, forms the subject-matter of application,Serial No. 255,901, for Letters Patent of the United States, filed by meand now pending, and need not, therefore, be more particularly describedherein.

In order that the triple valve may perform the additional functionsrequisite in the practice of my present invention, it has been providedwith certain additional members, as hereinbefore described, consistingof slidevalve 32, discharge-port 35, chamber 36, and channels 37 and 38.In other respects the triple valve, though modified in construction,accords in all substantial particulars with the Westinghouse triplevalve, as modified by other improvements for which I have filedapplication for Letters Patent of the United States, as hereinbeforereferred to.

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In the operation ot' the brake mechanism, as above described, air fromthe Inain reservoir and main air-pipe passes through the passages andchambers 1, 3, 4, 5, and 6 into chamber 7, forcing the piston 1l to theupper extremity of its stroke and uncovering a small feedinggroove, 8,inthe piston-chamber, through which air passes into the auxiliaryreservoir through chamber 9 and channel 10 until the pressures in theauxiliary reservoir and inthe main air` pipe are equal, the brakeJAcylinder being meanwhile in communication with the atmosphere throughchannel 1G, groove 17, discharge-port 1S, and exhaust-outlet 19.

To apply the brakes in making ordinary stops, a portion of the air isdischarged from the mainv air-pipe by the engineers valve, therebycorrespon dingly red uci ng the pressure inthe main air-pipe, whereuponthe higher pressure in the auxiliary reservoir causes the piston 11 todescend, covering the feedinggroove 8 and severing the connectionbetween the auxiliary reservoir and the main air-pipe. r1`hemotionofpiston 11 will now be governed by the diiference in the airpressureson its opposite sides, and the higher pressure in the auxiliaryreservoir will make it continue to descend until arrested by thedecrease of pressure in the auxiliary reservoir or by graduat ing-piston39. XVith ailuid-pressiue-actuated graduating-piston the stem ot' pistonmay be caused to arrest the downward motion of piston 11 sooner and withbetter results than with thespring-actuatedgraduating-stem. Ifchannel 23is left open in the two or three last cars of a train and closed in allthe other cars, it will readily be seen that air will pass from the mainair-pipe to the brake-cylinder on the two or three last cars only,lowering piston 11 on these cars more than on the other ears, therebyresulting in a greater application of brake-pressure en the rear carsthan elsewhere, and having a consequent tendency to eliminate impactorshock, which is the result when the rear cars only get the sameapplication of brake-pressure as on the forward cars, while theapplication does not take place as soon as on theforward cars. In itspreliminary downward traverse, piston 11 opens slide-valves 12 and 20 bywithdrawing their grad uatiugvalves 13 and 2l, respectively, while itkeeps slide-valve 32 closed during its descent by pressinggraduating-valve 33 tightly to its seat. \Vhen the pressure of air inthe auxiliary reservoir has been reduced by expansion into thebrake-cylinder till the pressure in the auxiliary reservoir and the mainair-pipe are equal, there is an equal pressure on both sides of piston11, and the additional pressure exerted by grad uating-piston 39 willcausepiston 11 to rise, forcing graduating-valves 13 and 21 to theirrespective seats, and thus closing slidevalves 12 and 20, at same timelifting graduating-valve 33 from its seat and opening slidevalve 32.\Vhen graduating -piston 39 has reached the upper extremity of itstraverse, port 34C in auxiliary slide-valve 32 must not by l suchtraverse have been carried past port 35. Port34 should either thenregister with port 35, or else should not have been moved far enough toregister with port 35. In the former case there will be an entirelyunobstructed communication between the main air-pipe and the auxiliaryreservoir through auxiliary slidevalve 32, ports 31 and 35, cavity 35,and channels 37, 38, and 10, and by means of this unobstructedcommunication the auxiliary reservoir can be recharged by a gradualincrease of pressure in the main ai r-pipe that is insu fficient to movepiston 1l.

lf port 34 should not have been moved far enough to register with port35 when the graduating-piston 39 has reached the upper extremity of itstraverse, then the gradual increase of pressure which is admitted intothe main air-pipe in order to recharge the auxiliary reservoir withoutreleasing the brakes will cause piston 11 to rise till port 3-1registers with port 35, when the auxiliary reservoir can be recharged,as in the former case, by a gradual increase of pressure in the mainair-pipe that is insufficient to move piston 11 farther.

\Vhenever it is desired to release the brakes, the full mainreservoir-pressare is admitted into the main air-pipe, which liftspiston 11 to the upper extremity of its traverse and establishescommunication between the brake-cylinder and the atmosphere throughchannel 16, valve-cavity or leakage-groove 17, port 18, and release-portor exhaust-outlet 19.

In the event of its becoming necessary to apply the brakes Awith greatrapidity and with their greatest available force, the engineer, by meansof his brake-valve,instantly discharges sufiicieut air from the frontend of the main airpipe to effect a sudden reduction of about twentypounds per square inch therein.where upon the piston 11 of the triplevalve is forced to the extreme downward limit of its stroke, carryingwith it the slide-valves 12 and 20, so that port 15 will register withchannel 16, and slide-valve 2O will pass below channel 24, with the sameresult as before,but diff eringin degree of the application ofthebrakes, which is much greater in the latter case. The discharge of airfrom the main air-pipe into the brake-cylinder, as controlled bythree-way cocks 49, takes place in every application of the brakes,however small, for the purpose of expediting the application of thebrakes and for eliminating impact or shock.

Tn using the terms triple valve 7 and triple-valve device I refer to avalve device, however specifically constructed, having a connection withthe main air or brake pipe; another with an auxiliary reservoir orchamber for the storage of power, and another with a brake-cylinder orits equivalent for the utilization of the stored power, and with arelease or discharge passage for releasing the operative power from thebrake-cylinder, whether the valves governing these passages orconnections are arranged in one or more cases IOO IOS

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and are moved by a piston or its equivalent,

or by a series of pistons or their equivalents, there being numerousexamples in the art of constructions varying materially in appearancewhereby those functions are performed, both in pressure and vacuum brakemechanlsms.

While I have herein described my invention as applied in a brakemechanism utilizing air under pressure, such as is in general andapproved use, I do not desire to limit myself to brakes so operated, asmyimprovements are likewise susceptible of application without variationof principle in connection with brakes worked by atmospheric pressure.Neither do I restrict myself to the exact construction here shown, Whilemechanical equivalents can be substituted in various other ways toaccomplish substantially the same results in sub- Stantially the sameway.

I am aware that there isin Patent No. 163,242 a construction which isclaimed to prod nce the Same results as myimprovement, and in whichthere is only one connecting-channel between main air-pipe and auxiliaryreservoir, which is controlled only by a check-valve, and suchconstruction, which involves an operation different from that of myinvention, I therefore hereby disclaim.

Having thus described my in vent-ion. I claim as new and desire tosecure by Letters Patent- 1. In a brake mechanism, a main air-pipe, anauxiliary reservoir, a brake-cylinder, and a triple valve, incombination with an auxiliary-valve device actuated `by the piston oftriple valve for admitting compressed air from the main air-pipe intothe auxiliary. reservoir through a secondary feed channel, pipe, orgroove for the purpose of recharging the auxiliary reservoir by means ofa gradual increase of pressure in the main air-pipe and Withoutreleasing the brakes, substantially as set forth. 2. In a brakemechanism, a main air-pipe, an auxiliary reservoir, a brake-cylinder,and a triple valve, in combination with an auxiliary-valve deviceactuated by .the piston of triple valve in such manner that thepreliminary upward traverse of said piston admits compressed air fromthe main air-pipe into the auxiliary reservoir through such auxiliary`valve device and a secondary feed channel,

pipe, or groove for the purpose of recharging the auxiliary reservoirby-means of a gradual increase of pressure in the main air-pipe andrwithout releasing the brakes, and which piston, by a further upwardtraverse, admits air from the main air-pipe into the auxiliary reservoirthrough the ordinary feed-groove simultaneously with the release ofthebrakes, substantially as set forth.

3. In a brake mechanism, a main air-pipe, an auxiliary reservoir, abrake-cylinder, and a triple valve, in combination with anauxiliary-valve device actuated by the piston of triple valve foradmitting compressed air from the main air-pipe into the auxiliaryreservoir through a secondary channel,"V pipe, or groove governed and.controlled by such valve device, as well as through the ordinaryfeed-groove in piston-chamber round edge of piston, in order that theauxiliaryreservoir may be recharged, when the brakes are applied, withor without the release of the brakes, as may be desired, substantiallyas set forth.

4. In a triple-valve device, a case or chest, a piston fixed upon a stemand Working in a chamber therein, a valve moving with the piston stemand governingports, and passages in the case leading to connections withan auxiliary reservoir, a brake-cylinder, and .to the atmosphere,respectively, an auxiliary valve actuated by the piston-stem andcontrolling communicationbetwecn passagesleadingtoconnections with amain air pipe and a brake-cylinder, respectively, in combination with asecond auxiliary valve actuated by the piston of triple valve andcontrolling a secondary communication between the main air-pipe and theauxiliary reservoir for the purpose of recharging the auxiliaryreservoir, when the brakes are applied, by means of a gradual increaseof pressure in the main air-pipe and without releasing the brakes,substantially as set forth.

55 The valve 32, actuated by piston 12, having graduating-valve 33 andport 34, in combi nation with port 35, cavity 36, and channels 37, 38,and 10, substantially as set forth.

GEORGE BAYLEY WILLIAMS.

NVitnesses:

HENRY C. STEvENs, Jol-IN J. HARTLEY.

